PURPOSES: The purpose of this study is to estimate the impact of variable message signage (VMS) on traffic safety as a function of road curve radius using statistical methods. METHODS: In order to analyze the impact of VMS installations on traffic safety, travel speed, lateral distance, and geometric data relating to road curvature in each study area was acquired and analyzed for the impact of providing VMS information on driver performance and traffic safety using statistical methods including student t-test, Mann-Whitney test, and the Anderson-Darling test for estimating traffic safety hazard zone in each lane. RESULTS: As a result of analyzing driver performance characteristics before and after providing VMS information, it was determined that by providing VMS information, mean travel speed is deceased and vehicles are driven with increased precision, following the centerline in the first and second lanes. Also the results of analyzing traffic safety impacts of VMS indicate that traffic safety performance factors in the first lane of the Gapyeong section can, on average, increase in the left and right side of the lane by 19.22% and 68.98%, respectively, and in the case of the second lane, safety impacts, on average, can increase in both sides by 100%. For the Hongcheon section, traffic safety impacts in the first lane, on average, can increase along the left and right sides of the lane by 32.31% and 47.18%, and within the second lane, traffic safety can be increased along the left and right side of the lane by 10.97% and -0.01%, respectively. CONCLUSIONS: Based on the results of this study, the impact on traffic safety obtained by providing VMS information for road sections with smaller curve radii is greater than can be obtained for road sections with larger curve radii.

차량의 주행속도는 설계일관성을 평가하는 주요한 척도로 활용되며 그 중 곡선반경은 여러 연구에서 공통적으로 제시한 주된 요인으로 나타났다. 이에 본 연구에서는 복합선형에서 설계속도별 적정 평면곡선반경 범위기준을 정립하고 운전자의 인지 행태를 나타낼 수 있는 인지반경을 정립하여 입체선형에서 적합한 평면곡선반경을 제시하고자 한다. 첫째, 본 연구에서는 저속차량의 방해요소를 최소화하기 위하여 입체선형을 고려한 도로의 임의지점에서 횡방향 미끄럼 마찰계수와 주행방향 미끄럼 마찰계수를 동시에 고려하여 설계속도와 종단경사별 평면곡선반경을 제시하였다. 둘째, 본 연구에서는 곡선부 인지반경을 통하여 평면 곡선부와 편평한 종단경사가 조합된 경우, 평면 곡선부와 종단곡선부가 조합된 경우를 비교한 후, 곡선부 인지반경을 산정하여 설계속도별 적정 평면곡선반경과 인지반경 비율을 제시하였다.

To evaluate the possibility of negative reaction at seismic isolation bearings subject to seismic load, seismic records of El-Centro and artificial earthquake wave were applied to a single-plate girder bridge with various analytical parameters of curvature radii and skew angles. It is found that seismic analysis using those parameters should be carried out to prevent negative reaction at support.